relates to the continuous casting of molten metals. It relates particularly to the continuous casting of molten metal between a pair of closely spaced, water-cooled rotating rolls whose axes lie horizontal and parallel to each other and rotate in opposite directions. Such continuous casting apparatus is commonly called a twin roll caster.
The continuous casting of molten metal using a twin roll caster is well-known. Such a process and apparatus was described and patented as early as 1865 in U.S. Pat. No. 49,053 to Bessemer. Since 1865 there have been many U.S. and foreign patents describing improvements in Bessemer's twin roll caster but to date, none of these prior twin roll casters have been able to produce long lengths of steel strip of acceptable commercial quality.
U.S. Pat. No. 4,784,209 to Hlinka, et al., assigned to Applicants' assignee, describes a modern twin roll casting apparatus.
One of the problems with prior twin roll casters has been the inability to accurately control the thickness of the metal strip in both the longitudinal and transverse direction as it is cast between the rolls. If the cast metal strip is to be acceptable for commercial use, it should have a predetermined and substantially uniform thickness from beginning to end and from edge to edge.